Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Denaturing solvents have been used to determine the molecular weight of the adrenocorticotropic hormone (ACTH) activity in mouse pituitary, in an ACTH secreting mouse pituitary tumor cell line (AtT-20/D-16v), and in the tissue culture medium from the pituitary tumor cells. ACTH activity was quantitated by radioimmunoassay and by bioassay. It is possible to utilize guanidine hydrochloride or sodium dodecyl sulfate in characterizing the multiple forms of ACTH because treatment of porcine ACTH (the 39 amino acid polypeptide form of ACTH, alpha(1-39)), pituitary extracts, tumor cell extracts, and tumor cell tissue culture medium with these denaturants does not diminish the immunological ACTH activity. Based on gel filtration in the presence of guanidine hydrocholoride, extracts of the pituitary tumor cells and the mouse pituitary contain three distinct molecular weight classes of ACTH activity. The major form of ACTH has a molecular weight similar to alpha(1-39) (molecular weight 4000-5500), but there are significant amounts of two higher molecular weight forms of ACTH: molecular weight 6500-9000 and molecular weight 20,000-30,000. The 6500-9000 molecular weight form of ACTH is the major form of ACTH in the tissue culture medium; there is no peak of alpha(1-39) size ACTH in the medium. In the radioimmunoasay all three forms of ACTH generate competitive binding curves parallel to that of porcine alpha(1-39); in the bioassay (stimulation of steroidogenesis in a mouse adrenal tumor cell line) the dose response curve for each of the molecular forms of ACTH is parallel to that for porcine alpha(1-39).
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PMID:High molecular weight forms of adrenocorticotropic hormone in the mouse pituitary and in a mouse pituitary tumor cell line. 16 85

The contributions of nuclear populations to the total profile of nuclear proteins in a tissue were examined in normal rat liver and Morris hepatoma 7777. Comparison by sodium dodecyl sulfate polyacrylamide gel electrophoresis of phenol-soluble nuclear proteins from tumor and control liver revealed additional proteins of molecular weight 60,000, 100,00, and 135,000 and the loss of proteins of about 45,000 and 55,000 in the tumor. Subfractionation of liver nuclei on a 30 to 50% sucrose gradient yielded three nuclear classes with nearly identical complements of the phenol-soluble proteins. Similar fractionation performed on the hepatoma nuclei also produced three nuclear populations. In the hepatoma nuclei, several differences in the phenol-soluble proteins were found between the minor, slowly sedimenting nuclear fraction, and the two major fractions, while the two latter fractions were very similar in their protein composition. Histones derived from both tissues were also compared electrophoretically, indicating a decrease in the concentration of histone H1(0)in all nuclear classes derived from the tumor.
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PMID:Fractionation of nuclei and analysis of nuclear proteins of rat liver and Morris hepatoma 7777. 17 Oct 58

High levels of a novel vitamin B12-binding protein (hepatoma B12 BP) have been observed recently in plasma obtained from three adolescent patients with hepatocellular carcinoma. This protein has now been isolated in homogeneous form from the plasma and pleural fluid of two of these patients by the use of affinity chromatography with vitamin B12-Sepharose. The hepatoma B12 BP belongs to the R-type group of B12-binding proteins and is essentially indistinguishable from the recently isolated human milk and saliva R-type proteins in terms of: (a) immunologic properties based on immunodiffusion and immunoprecipitation assays; (b) amino acid composition; (c) molecular weight based on amino acid and carbohydrate content; and (d) absorption spectra. Both hepatoma B12 BPs contain more sialic acid and less fucose than the milk and saliva B12 BPs. All four proteins contain similar amounts of galactose, mannose, galactosamine, and glucosamine. Differences in sialic acid content appear to account for the differences in electrophoretic mobility that were observed among the four proteins. Differences in total carbohydrate content appear to account for the differences in apparent molecular weight that were observed with both gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Tumor tissue from one of the patients contained 10 times as much R-type protein as did normal liver tissue from the same patient. This suggests, although it does not prove, that synthesis by the tumor is the cause of the high levels of R-type protein found in the plasma of certain patients with hepatocellular carcinoma. Plasma survival studies performed with rabbits indicate that the hepatoma B12 BP has a prolonged plasma survival and suggests that his parameter is also of importance.
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PMID:Isolation and characterization of a novel vitamin B12-binding protein associated with hepatocellular carcinoma. 17 Dec 83

The tumor (T) antigen of simian virus 40 (SV40)-transformed SV3T3 cells was immune precipitated with T antiserum obtained from hamsters bearing SV40-induced tumors and with rabbit antiserum to hamster cells. The resulting antigen-double antibody complexes were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Host components of SV40 T antigen with molecular weights of 70,000 and 30,000 were detected.
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PMID:Simian virus tumor antigen: a virus-specific and preexisting cell protein. 17 28

Urinary excretions of free cortisol and corticosteroid sulfates were determined in 31 female controls, 77 breast cancer patients, 14 cases of colonic cancer, and 7 patients with bronchial carcinoma. Elevated corticosteroid sulfate excretion was present in 38% of patients with locally recurrent breast cancer and 30% of those with distant metastases, but in only 13% of the "early" breast cancer cases. A similar abnormality was seen in colonic cancer. Urinary free cortisol was usually normal. ACTH stimulation in a normal subject produced marked increases of both urinary free cortisol and corticosteroid sulfates. It is concluded that elevated corticosteroid sulfate excretion in cancer patients arises from an increased cortisol production rate combined with increased sulfurylation of the steroid. In bronchial carcinoma patients, changes similar to those occurring in the ACTH-treated normal subject may have resulted from ectopic ACTH production in the tumor.
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PMID:The urinary excretion of corticosteroid sulfates by cancer patients. 17 59

The urinary excretion of corticosteroid sulfates and free cortisol were determined in 150 breast cancer patients. Four of 60 cases of early breast cancer (7%) and 26 of 90 patients with advanced breast cancer (29%) showed an elevated urinary corticosteroid sulfate excretion. Urinary free cortisol was usually normal. Estrogen receptor assays were performed on tumor samples from 67 breast cancer patients; 24 were from primary lesions obtained at mastectomy, 3 from inoperable primaries in patients with systemic metastases, and 40 from metastases. Sixteen of the primary breast cancers (67%), 26 of the metastases (65%) and 1 of the 3 inoperable primaries contained estrogen receptors. With 2 exceptions, patients with an increased urinary corticosteroid sulfate excretion also had estrogen receptor-containing tumors.
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PMID:Corticosteroid sulfate excretion and estrogen receptors in breast cancer. 17 41

1. The lipoproteins of the Ehrlich ascites tumor plasma were separated into 3 distinct fractions, very low density, low density and high density lipoproteins by preparative ultracentrifugation combined with agarose column chromatography. 2. High density lipoproteins contained 74% of the total protein in the lipoproteins. By contrast, most of the lipids were present in the very low density lipoprotein fraction. 3. The fatty acid compositions of the cholesteryl esters were appreciably different in the very low, low and high density lipoproteins, whereas phospholipid and triacylglycerol fatty acid compositions were quite similar in the 3 lipoprotein fractions. 4. Very low and high density apoprotein electrophoretic patterns on sodium dodecyl sulfate-acrylamide gels were similar to those observed in the corresponding lipoprotein fractions obtained from other mammalian species. The low density fraction, however, contained 7 apoprotein bands, and 32% of the low density apoprotein was soluble in tetramethyl urea. 5. The average molecular weights as determined by analytical ultracentrifugation were 2-10(7) (very low density), 6-10(6) (low density) and 4.4-10(5) (high density).
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PMID:Characterization of the Ehrlich ascites tumor plasma lipoproteins. 17 49

Mitochondria isolated from spontaneous and transplanted mammary adenocarcinomas of two strains of mice were compared, by various biochemical criteria, to mitochondria from mammary glands of midpregnant or hormonally stimulated, cancer-free mice. The specific activities of several mitochondrial enzymes including cytochrome oxidase, alpha-glycerophosphate oxidase, and succinate dehydrogenase were twofold to threefold lower, whereas the activity of monoamine oxidase was two fold higher in tumor mitochondria. Malate dehydrogenase, adenylate kinase, and NADH oxidase showed similar levels of activity in tumor and midpregnant mammary gland mitochondria. In addition, mitochondrial polypeptide composition was analyzed by electrophoresis on sodium dodecyl sulfate-urea polyacrylamide gels. Midpregnant mammary gland and mammary tumor mitochondria were similar in polypeptide composition; however, several differences were observed. A high-molecular-weight polypeptide, present in mid-pregnant mammary gland mitochondria was absent from tumor mitochondria. Also, tumor mitochondria contained an additional high-molecular-weight polypeptide not found in the midpregnant mammary gland. There were numerous differences in the relative proportions of many polypeptides common to both tumor and midpregnant mammary gland mitochondria.
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PMID:Biochemical studies on mitochondria isolated from Normal and Neoplastic Tissues of the Mouse Mammary Gland. 17 82

A 15-year-old girl with primary amenorrhea, hirsutism, and enlargement of the clitoris was found to have an increased titer of the urinary neutral 17-ketosteroids which failed to decrease after the administration of dexamethasone and an adrenal tumor was demonstrable on venography. Analysis of the adrenal venous effluent revealed gradients on the side of the tumor for testosterone, androstenedione, estradiol, and dehydroepiandrosterone sulfate. Following removal of the tumor, the hirsutism improved markedly, the menses returned, and sexual maturation progressed.
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PMID:Virilizing adrenocortical adenoma studied by selective adrenal venography. 17 82

In order to demonstrate a collagenolytic enzyme in a tumor, solid Tawa sarcoma was subjected to a tissue culture technique. Salt- and acid-soluble collagen used as substrate was extracted from the rat skin and tail tendon. The tumor mass used was obtained on the 5th, 8th, and 11th days after subcutaneous transplantation of ascites Tawa sarcoma cells. Each tissue fragment in the inner and outer layers of the tumor mass was incubated on collagen gel at 37 degrees for 4 days, and collagenolytic activity was determined by comparing the relative content of hydroxyproline in the attacked collagen which was separated by means of centrifugation. All fragments were found to possess collagenolytic activity with some variation. Higher activity was observed in the outer layer than in the inner layer. Tumor fragments were cultured, and the collagenolytic enzyme was isolated from the culture medium and concentrated by ammonium sulfate precipitation and acrylamide disc electrophoresis. Collagenolytic enzyme activity was examined for its mode of attack on native collagen.
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PMID:Collagenolytic enzyme in solid Tawa sarcoma. 17 66


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